1. Field of the Invention
The present invention generally relates to cassette cases and, more particularly, is directed to a video cassette case having hard plastic sheets on flat surfaces thereof and in which a tape cassette or video cassette is housed.
2. Description of the Prior Art
As a cassette case for accommodating therein a tape cassette such as a video cassette or the like, a cassette case made of a paper board or polypropylene (hereinafter simply referred to as a PP) and so on has been frequently utilized hitherto. FIG. 1 shows a conventional video cassette case 2 for accommodating therein a video cassette. In this video cassette case 2 of substantially rectangular shape having a cassette inserting opening 4 formed on one side thereof and cassette withdrawing grooves 3 formed on left and right side walls thereof, a video tape cassette 1 which is not yet used, for example, is inserted from the cassette inserting opening 4 into the video cassette case 2 to be housed therein. Then, the video cassette case 2 is covered on its whole surface with a packaging film 5 and the video cassette case 2 is delivered from the factory. In FIG. 1, reference numeral 6 designates a peel tape which is used to peel the packaging film 5 from the whole surface of the video cassette case 2.
As explained in connection with FIG. 1, if a manufacturing cost of the video cassette case 2 made of paper board, PP and the like is reduced, then such video cassette case 2 will become thin and weak. For this reason, if gaps 7, 7, . . . exist between the video cassette case 2 and the video tape cassette 1, then the video cassette case 2 will be wrinkled due to contraction of the packaging film 5 as shown in FIGS. 2A, 2B and 2C. In the video cassette case 2 shown in FIG. 2A, upper and lower side walls 9 and 10 are deformed in convex shapes 8a and 8b in the cassette insertion opening 4 due to the packaging film 5 and a distance L.sub.1 between vertexes of these convex shapes 8a and 8b becomes shorter than a length L (see FIG. 1) of the longitudinal direction of the video tape cassette 1, which makes it difficult to insert the video tape cassette 1 into the video cassette case 2. Similarly, in the video cassette case 2 shown in FIG. 2B, the width of the cassette insertion opening 4 is increased at its central portion between the left and right side walls 11 and 12 and decreased at its upper and lower portions between the left and right side walls 11 and 12 so that a width A of the cassette insertion opening 4 at its central portion is increased as compared with a width A' of the insertion opening 4 at its upper and lower portions. Further, in the video cassette case 2 shown in FIG. 2C, the width A of the cassette insertion opening 4 at its central portion is reduced as compared with the width A' of the insertion opening 4 at its upper and lower portions. In either case, the sizes L.sub.1, L.sub.2 and L.sub.3 in the longitudinal direction of the video cassette case 2 become smaller than the size L in the longitudinal direction of the video tape cassette 1. Also, the size A' of the insertion opening 4 at its upper and lower portions shown in FIG. 2B and the size A of the insertion opening 4 at its central portion shown in FIG. 2C become smaller than the lateral width of the video tape cassette 1. There is then the disadvantage that it becomes difficult to insert the video tape cassette 1 into the video cassette case 2 through the cassette insertion opening 4.